1. Field
The present application relates generally to wireless communications, and more specifically to systems, methods, and devices for reducing acknowledgment message (ACK) overhead.
2. Background
In many telecommunication systems, communications networks are used to exchange messages among several interacting spatially-separated devices. Networks may be classified according to geographic scope, which could be, for example, a metropolitan area, a local area, or a personal area. Such networks would be designated respectively as a wide area network (WAN), metropolitan area network (MAN), local area network (LAN), wireless local area network (WLAN), or personal area network (PAN). Networks also differ according to the switching/routing technique used to interconnect the various network nodes and devices (e.g. circuit switching vs. packet switching), the type of physical media employed for transmission (e.g. wired vs. wireless), and the set of communication protocols used (e.g. Internet protocol suite, SONET (Synchronous Optical Networking), Ethernet, etc.).
Wireless networks are often preferred when the network elements are mobile and thus have dynamic connectivity needs, or if the network architecture is formed in an ad hoc, rather than fixed, topology. Wireless networks employ intangible physical media in an unguided propagation mode using electromagnetic waves in the radio, microwave, infra-red, optical, etc. frequency bands. Wireless networks advantageously facilitate user mobility and rapid field deployment when compared to fixed wired networks.
The devices in a wireless network may transmit/receive information between each other. As part of this communication process, a device that receives information from another device may transmit an acknowledgment (ACK) to the device that transmitted the information, the ACK acknowledging the fact it received the information. The act of transmitting an acknowledgment adds additional overhead to communications in the wireless network.
This additional overhead may be especially problematic in some wireless networks. For example, in some areas, such as in Europe, some spectrums (e.g., wireless channels, frequency bands, etc.) have a transmit duty cycle restriction of 100 seconds per hour. That means that a given transmitter is only allowed to transmit in that spectrum for less than 100 seconds in a given hour. In some cases, such as for devices collecting measurements from sensors, the overhead of sending an ACK alone may exceed this duty cycle threshold. Thus, improved systems, methods, and devices for communicating ACKs are desired.